Processing of photographic silver halide photosensitive material and fixer used therein

Abstract

Photographic silver halide photosensitive material is processed, after exposure, by treating it with a working fixer solution. The photosensitive material comprises at least one layer of silver halide emulsion on a support and contains at least 10% by weight, based on gelatins, of a gelatin having an isoelectric point of at least 5.0 on the emulsion layer side. The working fixer solution is prepared by furnishing a fixer concentrate of at least pH 5 containing a thiosulfate as a fixing agent, 0.05-0.8 mol/liter of a sulfite and up to 0.01 mol/liter of a water-soluble aluminum salt, and diluting the fixer concentrate with water, thereby forming the working fixer solution containing a minimized amount of ammonium thiosulfate and 0.5-2.5 mol/liter of sodium thiosulfate. The method provides improved rapid processing with increased degrees of fixation and drying while preventing the generation of sulfurous acid and ammonia gases.

We claim: 
     
       1. A method for processing a photographic silver halide photosensitive material having at least one layer of silver halide emulsion on a support after exposure comprising the step of treating the material with a working fixer solution, wherein said working fixer solution is prepared by   furnishing a fixer concentrate of at least pH 5 containing a thiosulfate as a fixing agent, 0.05 to 0.8 mol/liter of a sulfite and up to 0.01 mol/liter of a water-soluble aluminum salt, and   diluting the fixer concentrate with water at a volume ratio of water to the concentrate of at least 0.5/1, thereby forming the working fixer solution containing up to 0.1 mol/liter of ammonium thiosulfate and 0.5 to 2.5 mol/liter of sodium thiosulfate; and   said photosensitive material contains at least 10% by weight of a gelatin having an isoelectric point of at least 5.0 on the same side thereof as the emulsion layer with respect to the support, in percent by weight of gelatins on the emulsion layer side.   
     
     
       2. The processing method of claim 1 wherein said working fixer solution is substantially of sodium thiosulfate. 
     
     
       3. The processing method of claim 1 wherein said photosensitive material has at least one layer of a silver halide emulsion which contains silver halide grains having a mean equivalent spherical diameter of up to 0.6 μm, is sensitive to radiation in the wavelength range of 600 to 800 nm, and adapted to be exposed to a light source in the form of a semiconductor laser. 
     
     
       4. The processing method of claim 1 which is carried out in an automatic processor including a developing tank, a fixing tank, a washing tank, a first rinsing tank between the developing and fixing tanks, and a second rinsing tank between the fixing and washing tank.